It seems that battery-electric buses are starting to come out of the woodwork and are being embraced by many municipalities around the world. Rather than discussing these in the hydrogen thread, I thought it would make sense to discuss battery electric buses in their own thread.

TreeHugger.com wrote:This milestone is important because once you pass the average driving range needed in a day by a bus, with a margin of safety on top, electric buses become ready for the big time:

Based on these test results, Proterra predicts its ten pack XR configuration (321kWh) will achieve 300 miles on a single charge. According to available General Transit Feed Specification (GTFS) data, typical urban and rural bus routes in the United States run less than 200 miles a day, bringing most routes within reach of Proterra’s current technology.

Part of the reason why the Proterra buses are doing this well is that they aren't just regular buses modified to be electric:

“The purpose-driven Catalyst design affords the best efficiency rating ever for a 40-foot transit bus, at 22 MPG equivalent,” said John Sleconich, Chief Engineer at Proterra. “Proterra buses are the only mass transit vehicle built from the ground up as an electric vehicle. With a unique aerodynamic body made from carbon fiber and advanced composite materials, we are able to reduce mass for maximum efficiency.”

According to this article, it appears that Worcester has the 100-kWh quick-charge version of the Proterra buses. I think the new high-capacity, NMC-based versions are just now being finalized and those will enter service (somewhere) in the very near future. I do think the high-battery-capacity version of the bus will be the one that nearly every municipality will prefer. It should be comparably-priced while allowing more buses to charge simultaneously at nighttime when most are not in service. The NMC batteries should also last significantly longer.

I'm becoming more-and-more convinced that NMC is THE Li-ion battery technology which will propel BEVs out of niche markets and into widespread adoption. We see it in the new LEAF as well as in this new version of the Proterra bus. In the bus arena, if BEVs can meet all of the rourte requirements while simultaneously lowering the total cost of ownership as well as providing all of the other obvious benefits of a BEV, then it seems clear that the diesels and natural gas incumbents will be replaced by BEVs at their EOL. As mentioned elsewhere, I see the newest, highest-capacity buses going on the longest routes while the older buses are used on progressively-shorter routes as their batteries degrade, thus giving the longest-possible battery life. That will be a major cost driver, but it should come down steadily as the technology matures.

BTW DNAinaGoodWay, have you ridden on one of the Worcester Proterra buses? If so, what was it like. Tony tells us that the electric buses in London are almost as noisy and rattly as their diesel counterparts.

DNAinaGoodWay wrote:Nope, haven't ridden a bus in my hometown in years. But probably most buses are noisy rattlers on the inside. Nature of the beast.

Perhaps, but I think by redesigning their bus from the ground up, Proterra may have been able to eliminate some of the NVH associated with the drivetrain and elsewhere. For instance, they use a purpose-designed two-speed transmission in their buses. In the video at their main webpage at the 1:20 mark, they claim theirs (the quick-charge version) is the lightest and quietest bus on the market at 57 dB. I don't know if that is inside or outside and how it is measured, but it is claimed to be an improvement.

DNAinaGoodWay wrote:Nope, haven't ridden a bus in my hometown in years. But probably most buses are noisy rattlers on the inside. Nature of the beast.

Electric buses would be less fatiguing to ride and drive with a smooth electric drivetrain. The mall manager had to build a concrete slab for the bus because asphalt would tear up with a bus idling on it.

ABB wrote:ABB, the leading power and automation technology group, announced today that it introduces an automated fast charging system which allows electric city buses to drive 24/7, thus enabling true zero emission bus transport in cities. With its automated rooftop connection and a typical charge time of 4–6 minutes, the system can easily be integrated in existing bus lines by installing fast chargers at end points, terminals, depots and/or intermediate stops. The modular design offering 150 kW, 300 kW or 450 kW of charging power provides any city bus with enough energy in only a few minutes to run its inner-city route continuously throughout the day.

Personally, I'm not convinced that quick-charging will win out over high-capacity batteries for BEV city buses. Even though the quick-charge approach should make the buses lighter, a much larger percentage of the charging will occur during the daytime when peak electrical demand occurs. Long-range BEV buses have the benefit of being charged overnight when there is less electrical load. Of course initially both types will find service until operators can decide which approach suits their municipality best.

In the future there may be a large amount of PV power on the grid, which may make daytime (quick) charging more attractive at that time.